Production of cyclic acetals

ABSTRACT

Formation of cyclic acetal compounds of the formula   BY REACTING A CARBONYL COMPOUND OF THE FORMULA R&#39;&#39;R&#39;&#39;&#39;&#39;C O with a second reactant which is   WHEREIN R&#39;&#39; and R&#39;&#39;&#39;&#39; are selected from the group consisting of hydrogen and an acyclic aliphatic hydrocarbon radical in the presence of a catalyst selected from the group consisting of compounds of Periodic Table Groups VB and VIB. For example acetaldehyde is reacted in liquid phase with ethylene oxide in the presence of molybdenum acetyl acetonate to form 2-methyl-1, 3-dioxolane.

United States Patent [191 Barone et al.

[ 1 Apr. 3, 1973 v [541 PRODUCTION OF CYCLIC ACETALS [75] inventors: Bruno J. Barone, Houston, Tex.;

William F. Brill, Skillman, NJ.

[ 73] 'Assignee: Petro-Tex Chemical Corporation,

- Houston, Tex.

22 Filed: Oct.16,1970

211 Appl. No.; 81,554

Primary ExaminerAlex Mazel Assistant ExaminerJaines H. Turnipseed Attorney-G. Baxter Dunaway [57] ABSTRACT Formation of cyclic acetal compounds of the formula by reacting a carbonyl compound 'of the formula R'R"C Q with a second reactant which is wherein R and R" are selected from the group consisting of hydrogen and an acyclic aliphatic hydrocarbon radical in the presence of a catalyst selected from the group consisting of compounds of Periodic Table Groups VB and VlB. For example acetaldehyde isreacted in liquid phase with ethylene oxide in the 7 presence of molybdenum acetyl acetonate to form 2- methyl-l, 3-dioxolane.

10 Claims, No Drawings PRODUCTION. OF CYCLIC ACETALS This invention relates to a method for the formation of compounds of the formula which comprises reacting .a carbonyl compound of the formula R'R"C. O with a second reactant whichis a member selected from the group consisting of and mixtures. thereof whereinR' and R" are-selected from the group consisting of hydrogen'andanacyclic aliphatic hydrocarbon radical'having from one .to 4 carbon atoms and in the presence of a catalyst selected fromthe group consisting of compounds, of Periodic Table'Groups VB and VIB.

The compounds of the, formula referred to hereafter as1glycols,used. as; reactants may be such as propylene glycol. or'other gly'cols within the definition. The compoundsof the formula HIV-C CR' R referred to hereafter as epoxides, may be such as isobutylene oxide, ethylene oxide, propylene oxide. or other epoxides within the definition. Thecompounds of the formula RR"C O, referred :to. hereafter as the car-' to about. 125C. A more preferred range of temperatui'es of reaction is from about 50C to about 70C. The reactions may be conducted at atmospheric pressure, at subatmospheric or super-atmospheric pressurelt is not believed that the pressure at which the reaction is conducted is critical. Free oxygen may be fed to the reaction zone or the reaction may be conducted in an oxygen atmosphere e.g. up to 500 p.s.i.g. or'higher. The reaction may be conducted under an inert gas, as nitrogen, under high vacuum, or in a system where the reactants are continuously refluxed. While solvents may be used,-they are not necessary and excess reactants may be used as the solvent. However, in some instances organic solvents such as benzene'or toluene hydrocarbon soluble compounds. Suitable catalysts are such as the complexes or chelate compounds including the acetyl' acetonates, soluble salts such as naphthenates or octoates- Other soluble compounds such as carbonyl compounds maybe suitably used. Ex-

amples of catalysts are molybdenum acetyl acetonate as catalysts are ineffective such as compounds of nickel,

bonyl compounds, may. be such asacrolein, methyl I ethyl ketone or other carbonyl compounds: within the definition. In these definitions!!! or'R'-' may he satu-.

rated or unsaturated or may be a combination of saturated and unsaturated radicals;

Typical reactions are the reaction of acetaldehyde with ethylene oxide or ethylene glycolv to form. 2- methyl-l, 3 dioxolane, acetaldehyde with 'isobutylene oxide or isobut'ylene glycol to form 2-methyl-4, 4

dimethyl-l ,3 dioxolane. Th'eepoxide or glycolreactant may be-formed in. situ from the corresponding olefin by adding oxygen to the reaction. For instance instead-of starting with propylene oxide the reactant may be propylene and the propylene oxide. is formed in-situ by oxidation with oxygen and if water or other source of hydroxyl ions is present the corresponding glycol will be formed as the reactant. Starting-olefinsmay be-such as propylene, n-butene-l, n-butene-Z, ixobutene, methyl butane, hexene-l and so forth.

The ratio of amounts. of epoxide,- glycol (or equivalent olefin precursor) and carbonyl-compound may be varied over a wide range, as. from about ll-l0 mol epoxide or glycol to one ,mol of, carbonyl com pound to l/"l0 mol of carbonyl compoundto one-mol-of epoxide or glycolbut approximately stoichiometric quantities to give the desired .1 cyclic acetal. are preferred.

The reactions are conducted in liquid 'phase preferably at temperatures. in the range of about 25C or-naphthenate.

lt has been discovered that certain other metal zinc, aluminum, lead, magnesium, copper, cobalt and manganese.

The cyclic acetals of the invention are useful as solvents and are particularly valuable because of their sta-.

bility towardalkalis. Also the cross linked products are useful as plasticizers. I

The following Examples are only illustrativej'All percents are by weight unless'expressecl otherwise. I

EXAMPLE 1 The following example illustrates thereaction of an;

unsaturated aldehyde, propylene:

A 500 ml. stainless steel autoclave was charged with 1 2.5 moles of acrolein, 2.6 moles of propylene and 0.5 g. of molybdenyl acetylacetonate. It washeated to 60 with stirring under 300 psi. of oxygen for 30 minutes. By analysis of the products by gas chromatography, it was found that 0.043 mole of olefin :had reacted to give- 2-vinyl-4-methyl dioxolane in a 98 percent selectivity.

EXAMPLE 2.

A solution of 0.05 mole each of acetaldehyde'and propylene oxide containing 0.05- g. of molybdenyl acetylacetonate and 0.008 mole of water. was allowed to react for 24 hours at 60C. Gas chromatographic.

analysis showed that percent of the aldehyde and percent of the'epoxide had reacted to give a theoretical yield'of cyclic acetal of 75 percent.

EXAMPLE 3 l7 Y HRC-CR" H and the rrn'c cn'n Examples 3 to 7 illustrate the invention. Examples 8 compound is formed in situ by the reaction of an olefin to 1? illustrate the failure of other metal compounds to of the formula HR'C=CR"H with oxygen to form the catalyze the reaction. said TABLE Time and Example Reactants Catalyst temp. Pressure Cyclic aeetal product 3 2.5 M aerolein, 2.5 M propylene 1.5 g. M0 uaphtlienate 2.0 lgogrs, %p.s.i. Z-vinyM methyl dioxolaue.

50 1. 2. 4 .05 M propylene oxide, .05 M 0.05 5:. Mo naplitlienute. 24 hours, Sealed {25%tra 2,4, dimetliyl-1,3 dioxolane.

aeetaldehydc. 00 C. tube. 10.7% e -.l,4 dimethyl-1,3 (lioxolane. 5 .05 M propylene oxide, .05 M aeetalile- .05 1;. M0. aeetyl aeetonate do.. do. {'1runs-2,4 di|nethyl-1,3 dioxolane.

hyde, .008 M water. Cis 2,4 dimothyl-l,3-dioxolane. 6 .1 M propylene blyeol, .1 M nerolein. .05 1;. Mo acetyl ueetonate "do do 62% 2 vinyl i-lnethyl dioxelanefi 7 .6 M propylene oxide, .5 M uerolein, .1 wt. percent zirconium aeetyl do .do. H. 2 vinyl-4nn-.l.hyl (lloxoluno.

05 M water. :teetonute. 8 do. M .1 wt percent nickel aeetyl do c (lo None deteeted.

- imetonate. EL de .1 wt. percent zine ueetyl do do Do.

eeotonate. 1O do .1 wt. percent aluminum aeetyl do. .do Do.

aeetonate. ll do .1 wt. percent plumbous aeetyl do do Do.

aeetonate. 12 .05 M propylene oxide, .05 M acrolein, .1 wt percent magnesium aoetyl d0 do Do.

- .05 M water. aeetonate. 13 do .1 wt .pereent cupric aeetyl do do Do.

acetona 12 .410 .1 wt. percent cobaltlc aeetyl do do Do.

acetonate. 15 ..do .1 wt. percent manganous acetyl .do do Do.

. aeetonate. 1G "do .1 wt. percent coballie aeetyl .do do Do.

acetonate. 17 dos... .1 wt. percent inangnnie neetyl do d0 l)o.

ueetonate.

l Selectivity based on cpoxide consumed. Selectivity based on glycol consumed.

We claim: 0 1. A method for the formation of compounds of the formula compound. 6. The method of claim 1 wherein the said catalyst is a compound of molybdenum.

R 7. The method of claim 1 wherein the said catalyst is molybdenum acetyl acetonate. which comprises reacting a carbonyl compound of th 8. The method of claim 1 wherein the said catalyst is formula RR"C=O with a second reactant which is a p hen member selected from the group consisting of 40 9. A method for the formation of compounds of the formula on on o\ l R' G-dlR/g or IlRC--CRII R,R,,C

I n I 0-CR" and mixtures thereof wherein R and R are selected f the group consisting of hydrogen and an acyclic which comprises reacting a carbonyl compound of the aliphatic hydrocarbon radical having from one to 4 carformula RIRIIC=O with a second f l which is a bon atoms in the presence of a catalyst selected from .{nember selected from the group conslstmg of the group consisting of compounds of molybdenum and OH OH 0 zirconium which are soluble in the reaction medium.

0 compound is aceta1dehyde and mixtures thereof wherein R and R" are selected The method of claim 1 wherein the said from the group consisting of hydrogen and an acyclic 0 compound is acroleim aliphatic hydrocarbon radical having from one to 4 car- 4. The method of claim 1 wherein the said mm P Presence of a molybdenum naphthenate catalyst.

0 I 9 compound is acetaldehyde and the I a compound is propylene oxide. 1 HR H 5. The method of claim 1 wherein the said second compound P py OXldereactant is s e s s e 10. The method of claim 9 wherein the said R'R"C= 

2. The method of claim 1 wherein the said R''R''''C O compound is acetaldehyde.
 3. The method of claim 1 wherein the said R''R''''C O compound is acrolein.
 4. The method of claim 1 wherein the said
 5. The method of claim 1 wherein the said second reactant is
 6. The method of claim 1 wherein the said catalyst is a compound of molybdenum.
 7. The method of claim 1 wherein the said catalyst is molybdenum acetyl acetonate.
 8. The method of claim 1 wherein the said catalyst is a naphthenate.
 9. A method for the formation of compounds of the formula
 10. The method of claim 9 wherein the said R''R''''C O compound is acetaldehyde and the 